Challenges Await Plan to Reduce Emissions

Jean Pieri/The St. Paul Pioneer Press, via Associated Press

A power plant in Becker, Minn. New coal or gas-fired plants would be required to capture carbon dioxide from the smokestacks and "sequester" it underground.

WASHINGTON — The Obama administration's potentially pathbreaking proposal for carbon emission limits on new power plants will face political and legal challenges from opponents who argue that the technology needed has not been close to being proven as the law requires.

The draft rule was announced on Friday at the National Press Club by Gina McCarthy, the administrator of the Environmental Protection Agency. But to protect industries from pie-in-the-sky requirements, current law limits what rules the agency can make.

E.P.A. rules sometimes demand technological advancements, but the goals that the agency establishes have to be met by techniques that existing law describes as "adequately demonstrated."

The proposal would limit new gas-fired power plants to 1,000 pounds of carbon dioxide emissions per megawatt-hour and new coal plants to 1,100 pounds of carbon dioxide. Industry officials say the average advanced coal plant currently emits about 1,800 pounds of carbon dioxide per megawatt-hour. A megawatt-hour is a little more than a typical American household uses in a month.

Once the rule is in place, new plants would be required to capture carbon dioxide from the smokestacks and "sequester" it underground. Officials said the regulation could be completed by the fall of 2014.

But, utilities say, laws governing underground disposal were not written with carbon dioxide in mind, and sequestration is in a legal quagmire.

Three systems of carbon capture are in various stages of development. The most common is to convert coal into a mixture of hydrogen, carbon monoxide — which in this context is a fuel, not a pollutant — and carbon dioxide, and to recover the carbon dioxide at two different stages.

Another method, demonstrated by the utility American Electric Power in recent years at its Mountaineer plant in West Virginia, is to burn coal conventionally and use an ammonia process to grab the carbon dioxide out of the flue gas. And if coal is burned in nearly pure oxygen, the flue gases are nearly pure carbon dioxide.

In the last few days, Ms. McCarthy has referred to several early-stage carbon capture projects as a sign that industry can build the needed equipment. In testimony on Wednesday before the House Energy and Power Subcommittee, Ms. McCarthy cited four such projects. She told reporters on Friday that the draft rule was based on "technologies that are already entering the market and being constructed in plants today." But the four she referred to in the committee hearing ranged from under construction to planned. None of them would sequester the carbon dioxide, and all would sell it.

The closest to opening is the Southern Company's Kemper County plant in Mississippi, which will convert coal to gases and then filter out some of the carbon dioxide, reducing emissions by about 65 percent.

But the plant, at $5 billion, is $1 billion over budget. Southern Company said in a statement on Friday that the plant's economics were peculiar to its location, and not a national model. Its captured carbon will be sold for use in the oil fields, where it helps force more oil to the surface.

But most power plants are not in areas where they can sell their carbon dioxide.

Revis W. James, director of the Energy Technology Assessment Center at the Electric Power Research Institute, said that before a technology could be considered commercially demonstrated, "you'd need Kemper to be operational and a couple more Kempers, and have the kinks worked out."

Carbon capture and sequestration, he said, was unlikely to be competitive unless natural gas prices increased by 100 to 150 percent and the construction of nuclear plants was ruled out.

Ms. McCarthy also referred to three projects that would sell carbon dioxide to the oil industry: a coal plant in Saskatoon, Saskatchewan, the Boundary Dam project, where the provincial utility plans to rebuild a small 45-year-old unit to capture carbon dioxide; the Texas Clean Energy Project, 15 miles west of Odessa, where the builders hope to soon break ground; and Hydrogen Energy California, proposed for the oil fields of Kern County.

As the price of oil has risen, so has the value of carbon dioxide to oil drillers. The value as a carbon-reduction mechanism is unclear, though, because the result is to produce more oil, all of which will be burned, producing more carbon emissions.

E.P.A. officials say that a carbon-emissions rule would push improvements in the technology. Two decades ago when the agency required technology to reduce emissions of a different pollutant — nitrogen oxides, a smog precursor — that, too, was expensive and not thoroughly demonstrated, but today it is routine, they said.

The biggest carbon-capture project to date was at the American Electric Power's Mountaineer plant in New Haven, W.Va. But Nicholas K. Akins, the company's chairman and chief executive, said that technology was "definitely not ready for prime time."

Mountaineer was a pilot project. Equipping the whole plant would have cost $1 billion, he said, and driven up costs per kilowatt-hour by 60 to 80 percent. The company eventually shut down the effort because it could not recover the costs from its customers. And injection of carbon dioxide into the earth was only possible because it was classified as a research project, he said.

Mr. Akins and other industry executives say that a rule governing new coal plants would have little impact because of the low price of natural gas. "No one in their right mind is going to start a coal unit at this point," he said.

But they fear it will become a precedent for limits on existing plants. Rules on smog, mercury and other pollutants are accelerating the retirement of many old coal plants, and a rule on carbon dioxide would hit many more, they say.

Many of the environmental groups that applauded the E.P.A.'s proposed standard appear to agree. They took pains to note that coal plants also emit a variety of smog-forming and toxic chemicals, and that suppressing new plants because of their carbon dioxide emissions would have the effect of reducing the other emissions, too.

On the other side, Senator Mitch McConnell, who is from coal-dependent Kentucky, promised to prevent the measure from being carried out. "The president's decision today is an escalation of the war on coal," he said.

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